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2 Sheets-Sheet 1.

ATTORNEY Patented Aug. 21, 1894.

W. H, DIXON. ROCK DRILL.

(No Model.

UNITED S To all whom it may concerns; Be it known that I, WILLIAM H. DIXON,"a citizen of the United States of America, residing at Denver, inthe county of Arapahoe and State of Oolorado,have invented'certain newand useful Improvements in Rock-Drills; and I do declare the followingto be a full, clear,

and exact description of the invention, such as will enable othersskilled in the art towhich it appertains to make and use the same,reference being had to the accompanying draw-' ings, and to the figuresof reference marked :hereon, which form a part of thisspecifica- Myinvention relates to improvements in rock drills specially designed foroperation by hand power; and the same consists'of the features,arrangements and combinationsfheral inafter described and claimed, allof which will be fully understood by reference to the accompanyingdrawings in which is" illustrated an embodiment thereof.

. In the drawings, Figure 1 is a top or plan view of the drill. Fig. 2is a sideelevation partly in section. Fig. 3 is an end elevation of thedrill, shown on a reduced scale, and in position for use. Fig. 4 is afragmentary view of the drill shown partly in section, and partly inside elevation. Fig.5 is a cross-seco tionof the frame, the ratchet madefast on the feed screw, and its operating mechanism, l being shown inelevation. Fig.6 is a rear, end elevation of the machine. Fig. 7 is across-section taken through the framework, the ram and the feed screw,on the line :1;-a:,

Figs. 1 and 2.

Similar reference characters indicate corresponding parts or elements ofthe mechanism in the several views.

Let the numeral 5 designate the stationary PATENT QFFIGE.

WILLIAM HJDIVXON, oF unrivnacoLonnno, ASSIGNOR, B DIRECT AND MESNEASSIGNMENTS,OF ELEVEN-SIXTEENTHS TO CHARLES E. GART- MAN ANDFRANK A.JOSLIN, or SAME PLACE.

ROCK-DLRILL.

srncrrrcA'rioiv forming part pe gram No. 624,993, dated August 21, 1894.

A Application filed February 27, 1894. Serial No. 501,744. (No model.)

groove of corresponding shape formed in the base or stationary frame 5.Upon the frame '6 is mounted the ram 12 which is journaled in boxes 13.This ram is surrounded by a coil-spring 14 which bears against a collar12 i at one extremity and a journal box 13 at the opposite extremity.One extremity of the ram carries a chuck 12 in which the drillingt'oolor bit 15 is inserted; while theopposite end of ,the ram carries aratchet head 16 en gaged by a forked frame 17 through which thereducedextremity of the ram passes. The. arms 17 of the fork engage groovesformed in the sides of the frame 6 in which tojform bearing surfaces forthe cams 18 mounted on the shaft 19 which is journaled in boxes 20 onframe 6.

shaft 19. As this shaft is rotated, the frame 17 is engaged by the cams18, whereby the ram is alternately forced backward and released. As theram is carried backward by der tension, while the recoil of the spring,as soon as the ram is released, carries the latter forcibly backward,and delivers the blow against the rock through the medium of the drillbit 15.

The necessary partial rotation of the drill bit between strokes isobtained through the instrumentality of actuating mechanism connectedwith the ratchet 16 of the ram; This fulcrumed on the frame 17; anactuating pawl 23 engaging the ratchet head, and to which the lever ispivoted; and a locking pawl 24 also engaging said head. The lever widestat its rear extremity; hence, every time the frame 17 moves backward(the cam being relatively stationary) the ram, together with the drillbit, is given a partial rotation preparatory to delivering the blow. Theforward longitudinal movement of the frame 6 tongue 6 centrally locatedand engaging a they are adapted to slide. The extremities ofthe arms areturned inward as shown at 17 Suitable hand cranks 21 are attached to thethe forked frame, the spring 14 is placed unactuating mechanism consistsof a lever 22 22 is in turn actuated by a cam 25 made fast on the frame6, and provided withan inclined face 25 engaging the lever. The cam 25is" naled in the ends of the frame 6 below the ram and engaging adivided nut 27 attached.

to the stationary frame 5. This screw shaft carries a ratchet disk 28which is engaged by a pawl 29 pivoted on alever 3O fulcrumed'on theframe 6 and having its free extremity located in the path of a cam 31made fast on [0 one arm of the frame 17. It will be observed that asthe'screw shaft 26 is actuated, the frame 6 is carried forward. Thisforward movement of the frame, however, doesnot determine the feed ofthe ram and drill bit; in other words, the frame 6 may get ahead of theram, since the forward movement of the latter is determined. by thestructure of the rock engaged by the bit. Now, if by reason of thehardness of the rock, the frame gets in advance, or toofar ahead of theram, the cam 31 will cease to engage the lever 30,.since the forwardmovement of the frame 17, at each stroke of the ram, islimited by themovement of the latter; hence the frame 6 will wait for the ram, so tospeak, until the latter has reached the proper position relatively tothe frame, when the cam 31 will again engage the lever 30, depress thepawl 29, impart a partial rotation to the screw shaft and move the frameHence the for- I ward movement of the frame 6 is automati- 0 6 forward acertain distance.

cally regulated to harmonize with the progress of the ram and drill bit,which will, of

' course, depend upon thecondition of the rock.

5 Mounted on the cam shaft 19, is a gear 32 From the foregoingdescription, the opera- .tion of my improved rock drillwillbereadilyunderstood. The cam shaft is rotated by the use of. the cranks 21. Thecams 18 are thus made to engage the extremities 17 of the forked frame17, whereby said-frame, and the ram, or reciprocating shaft 12,'arealternately carriedbackward and suddenly released. As .soon as the ramis released, the recoil-of the spring 1 L carries it forcibly forward.As the frame-17 reeiprocates, the feed mechanism,

' and the mechanism for imparting the partial rotation to the ram anddrill bit, are operated. Having thus described my invention, what Iclaim is In a rock drill, the combination with the movable andstationary frames, of the springactuated ram slidingly mounted on themovable frame, a frame 17 sliding-1y attached to the movable frame andre'ciprocati'ng with the ram to which it is attached, and feed mechanismconsisting of a screw shaft journaled in the movableframe and carrying aratchet disk, a nut made fastlin the stationary frame and through whichsaid s'haf-t passes, a lever fulcrumed on the movable frame, apa'wlpivoted on the lever and engaging the ratchet disk, and a cam consistingof a plate attached WILLIAM H; DIXON.

Witnesses:

G. J. ROLLANDET, CHAS. E. DAWsoN.

